drm/i915: Dynamically allocate the CRC circular buffer

So we don't eat that memory when not needed.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_debugfs.c

@@ -1822,6 +1822,12 @@ static int pipe_crc_set_source(struct drm_device *dev, enum pipe pipe,
 
 	/* none -> real source transition */
 	if (source) {
+		pipe_crc->entries = kzalloc(sizeof(*pipe_crc->entries) *
+					    INTEL_PIPE_CRC_ENTRIES_NR,
+					    GFP_KERNEL);
+		if (!pipe_crc->entries)
+			return -ENOMEM;
+
 		atomic_set(&pipe_crc->head, 0);
 		atomic_set(&pipe_crc->tail, 0);
 	}
@@ -1847,6 +1853,12 @@ static int pipe_crc_set_source(struct drm_device *dev, enum pipe pipe,
 	I915_WRITE(PIPE_CRC_CTL(pipe), val);
 	POSTING_READ(PIPE_CRC_CTL(pipe));
 
+	/* real source -> none transition */
+	if (source == INTEL_PIPE_CRC_SOURCE_NONE) {
+		kfree(pipe_crc->entries);
+		pipe_crc->entries = NULL;
+	}
+
 	return 0;
 }
 

drivers/gpu/drm/i915/i915_drv.h

@@ -1232,7 +1232,7 @@ struct intel_pipe_crc_entry {
 
 #define INTEL_PIPE_CRC_ENTRIES_NR	128
 struct intel_pipe_crc {
-	struct intel_pipe_crc_entry entries[INTEL_PIPE_CRC_ENTRIES_NR];
+	struct intel_pipe_crc_entry *entries;
 	enum intel_pipe_crc_source source;
 	atomic_t head, tail;
 };